I have read the assertion on other posts that if the entanglement of one photon of an entangled triplet is broken then the whole system collapses and the remaining two are no longer entangled, has this been shown to be true? If this is the case then would this not breach the laws around FTL communication?

I am imagining an entangled triplet with one particle being transported e.g. on a mars space rover. At the point of landing the rover destroys the entanglement meaning that the disruption in the entanglement between the two remaining particles is observed here on Earth confirming landing as opposed to waiting 5-20 minutes for radio communication. But this cannot be possible as it would constitute FTL communication.